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Evaluation of wild cabbage (Brassica incana) varieties tolerance to abiotic stress factors
No full textKlimatske promjene i s njima često povezan abiotički stres imaju vrlo značajan utjecaj na rast i razvoj
biljaka. Za suočavanje s nepovoljnim uvjetima u okolišu biljke koriste različite strategije i mehanizme
kako bi smanjile njihov negativan učinak. U ovom istraţivanju ispitano je šest varijeteta divljih
kupusa (Brassica incana) koji prirodno rastu na liticama hrvatskih otoka u izuzetno nepovoljnim
uvjetima. Klijanci uzgajani na 1 %-tnom agaru bili su podvrgnuti solnom (100 mM NaCl),
osmotskom (200 mM manitol) i temperaturnom (maksimum na 40 °C) stresu, te kombinaciji
navedenih vrsta stresova. Dobiveni rezultati usporeĎeni su s tri varijeteta, morfološki vrlo slične,
raštike (Brassica acephala var. capitata) koji su tretirani na isti način kao i divlji kupus. Odgovor
biljaka na stres pratio sam testom inhibicije rasta te mjerenjem biokemijskih markera stresa. Na
osnovu dobivenih rezultata odabrao sam dva varijeteta divljeg kupusa i dva varijeteta raštike na
kojima sam dodatno, pomoću metode qPCR, pratio ekspresiju gena (NAC041, NAC084 i DREB2A)
uključenih u odgovoru biljaka na stres. Temperaturni tretman je kod mjerenja biomase imao najmanji
utjecaj na rast i razvoj, dok je najveće smanjenje uzrokovao osmotski stres. Kod divljeg kupusa je na
svim tretmanima, a posebno na solnom i osmotskom, zapaţeno povećanje sadrţaja prolina. Različiti
varijeteti divljih kupusa pokazali su različite antioksidativne odgovore na svakom tretmanu, dok se
razina malondialdehida (MDA) u najviše slučajeva povećavala kod solnog stresa. Povećana
akumulacija ukupnih fenola u divljih kupusa zabiljeţena je kod solnog i osmotskog stresa. Tretmani
koji su uključivali temperaturu su u najvećem broju slučajeva uzrokovali povećanu ekspresiju gena
NAC, a ekspresija gena DREB2A bila je zabiljeţena na svim tretmanima što opravdava njegovu ulogu
u otpornosti na stres.Climate changes and the often associated abiotic stress have a very significant impact on the growth
and development of plants. To cope with adverse environmental conditions, plants use different
strategies and mechanisms to reduce their impact. In this research, six varieties of wild cabbage
(Brassica incana) that grow naturally on the cliffs of Croatian islands in extremely unfavorable
conditions were examined. Seedlings grown on 1% agar were subjected to salt (100 mM NaCl),
osmotic (200 mM mannitol) and temperature (maximum at 40 °C) stress, as well as a combination of
these types of stress. The obtained results were compared with three varieties, morphologically very
similar, kale (Brassica acephala var. capitata) which were treated in the same way as wild cabbage.
I monitored the plants response to stress with a growth inhibition test and by measuring biochemical
markers of stress. Based on the obtained results, I selected two varieties of wild cabbage and two
varieties of kale on which I additionally monitored the expression of the stress responsive genes
(NAC041, NAC084 and DREB2A) by using PCR. Temperature treatment had the least impact on
biomass measurement, while osmotic stress caused the strongest reduction. In wild cabbage, an
increase in proline content was observed in all treatments, particularly salinity and osmotic stress.
Different varieties of wild cabbage showed different antioxidative responses to each treatment, while
the level of malondialdehyde (MDA) increased in most cases under salt stress. Increased
accumulation of total phenols in wild cabbage was recorded under salt and osmotic stress. Treatments
that included temperature caused increased NAC gene expression in most cases, and DREB2A gene
expression was recorded in all treatments, which justifies its role in stress resistance
Measurements of jet quenching using semi-inclusive hadron+jet distributions in pp and central Pb-Pb collisions at √sNN = 5.02 TeV
No full textThe ALICE Collaboration reports measurements of the semi-inclusive distribution of charged-particle jets recoiling from a high transverse momentum (high pT) charged hadron, in pp and central Pb-Pb collisions at center-of-mass energy per nucleon–nucleon collision √sNN = 5.02 TeV. The large uncorrelated background in central Pb-Pb collisions is corrected using a data-driven statistical approach which enables precise measurement of recoil jet distributions over a broad range in pT,ch jet and jet resolution parameter R. Recoil jet yields are reported for R = 0.2, 0.4, and 0.5 in the range 7 < pT,ch jet < 140 GeV/c and π/2 < ϕ < π, where ϕ is the azimuthal angular separation between hadron trigger and recoil jet. The low-pT,ch jet reach of the measurement explores unique phase space for studying jet quenching, the interaction of jets with the quark–gluon plasma generated in high-energy nuclear collisions. Comparison of pT,ch jet distributions from pp and central Pb-Pb collisions probes medium-induced jet energy loss and intra-jet broadening, while comparison of their acoplanarity distributions explores in-medium jet scattering and medium response. The measurements are compared to theoretical calculations incorporating jet quenching
Litho- and biofacies characteristics of the Upper Jurassic carbonate deposits - Rovinj, Zlatni rt
No full textJadranska karbonatna platforma (AdCP) jedna je od najvećih platformi tijekom razdoblja mezozoika u području Tetisa. Istra kao dio AdCP–a pripada njenom sjeverozapadnom dijelu te je geološki podijeljena u pet megasekvencija koje su odijeljene vremenski dužim ili kraćim prekidima taloženja. Na istraživanom lokalitetu Zlatni Rt ukratko je opisana jedna od površina subaerskog izlaganja. Lito– i biofacijesne značajke podinskih (kimeridž) i krovinskih (titon) naslaga upućuju na kontakt prve i druge megasekvencije. Starost naslaga je dokazana mikrofosilnim zajednicama koje su prepoznate u izdvojenim litofacijesima te prepoznatom površinom diskontinuiteta.Adriatic Carbonate Platform (AdCP) was one of the biggest platforms during the Mesozoic era in the Tethys region. Istria as a part of AdCP belongs to its northwestern part and it is geologically divided into 5 megasequences separated by long and short periods of deposition. One of the subaerial exposure surfaces at the researched site Zlatni Rt is briefly described. Lithofacies and biofacies features of the underlying (Kimmeridgian) and overlying (Tithonian) deposits indicate the contact between the first and second megasequences. The age of the deposits has been proven by microfossil assemblages identified in distinct lithofacies and by the recognized surface discontinuities
PETROLOGY OF EOCENE CONGLOMERATES FROM ZRINSKA GORA
No full textU svrhu određivanja petroloških karakteristika eocenskih sedimentnih naslaga Zrinske gore u blizini zaseoka Lovča snimljen je sedimentološki stup i prikupljeni su uzorci reprezentativnih valutica konglomerata i pješčenjaka. Uzorci su proučavani metodom optičke mikroskopije u prolaznom svjetlu. Na temelju mineraloških i strukturnoteksturnih karakteristika prikupljene valutice podijeljene su u 12 litotipova različitih magmatskih intruzivnih i efuzivnih, vulkanoklastičnih, kataklastičnih i metamorfnih stijena. Pješčenjaci su određeni kao litoareniti filosilikatnog i hematitnog veziva s litoklastima stijena koje se pojavljuju i u valuticama. U kontekstu razvoja paleocenskoeocenskog taložnog bazena duž Savske zone razmotrena je provenijencija valutica konglomerata i njihova sličnost s eocenskim konglomeratima drugih područja. Valutice granofira te sijenita i monzonita ukazuju na podrijetlo iz Savske zone, valutice efuziva i vulkanoklastita ostavljaju mogućnost miješanog podrijetla iz više mezozojskih kompleksa, a valutice metamorfnih stijena odgovaraju predeocenskim stijenama srednjeg i visokog stupnja regionalnog metamorfizma iz šire okolice Zrinske gore.To ascertain the petrological characteristics of the Eocene sedimentary deposits of Zrinska Gora, near the village of Lovča, a sedimentological column was recorded, and representative samples of conglomerate pebbles and sandstones were collected. The samples were examined using the method of optical microscopy of transmitted light. The collected pebbles were classified into 12 lithotypes of various magmatic, volcaniclastic, cataclastic, and metamorphic rocks, based on mineralogical and structural-textural characteristics. The sandstones were determined as lithoarenites with phyllosilicate and hematite binding, containing rock fragments from lithologies present in the pebbles. Regarding the development of the Paleocene-Eocene sedimentary basin along the Sava zone, discussions revolved around the provenance and similarities of conglomerate pebbles to those found in Eocene conglomerates from adjacent areas. Specifically, pebbles of granophyre, syenite and monzonite suggest a Sava zone origin, while those composed of volcanic rocks could be of a mixed origin from various Mesozoic complexes. Additionally, pebbles of metamorphic rocks align with pre-Eocene formations showing medium to high degrees of regional metamorphism across the broader area
DISTRIBUTION OF BECHSTEIN'S BAT (Myotis bechsteinii) IN THE CONTINENTAL BIOGEOGRAPHICAL REGION OF THE REPUBLIC OF CROATIA - INDICATOR SPECIES FOR FOREST HABITAT MANAGEMENT
No full textU istraživanjima je analizirana rasprostranjenost velikouhog šišmiša (Myotis bechsteinii),
rijetke i važne indikatorske vrste za očuvanost šumskih staništa, na području kontinentalne
biogeografske regije u Hrvatskoj. Intenzivnim terenskim istraživanjima zabilježeno je 12 novih
lokaliteta, čime je značajno povećano poznavanje areala rasprostranjenosti vrste. Analiza
aktivnosti vrste pokazala je da koristi mozaičnu strukturu staništa, ali s dominantnim udjelom
listopadnih šumskih staništa, unutar kojih dominiraju sastojine starih stabala bukve (63 %) i
hrasta (32 %). MaxEnt model povoljnosti staništa identificirao je temperaturne bioklimatske
varijable kao značajnije od oborinskih, uz značajan doprinos i blizine vodenih staništa.
Podudaranje nezavisnih podataka o prisutnosti vrste s višim kategorijama modelirane
povoljnosti bilo je dobro, potvrđujući upotrebljivost modela. Ustanovljena je i podudarnost
viših kategorija povoljnosti modela s terenski istraženim lokalitetima prisutnosti vrste u
najvećem udjelu bukovih i hrastovih šuma. Predložene su mjere gospodarenja šumama s ciljem
očuvanja populacija šišmiša vezanih uz šumska staništa.This thesis is a result of research and analysis of the distribution of the Bechstein’s bat (Myotis
bechsteinii), a rare and important indicator species for the conservation of forest habitats, in the
continental biogeographic region in Croatia. Altogether 12 new localities were recorded
through intensive field research, which significantly increased the knowledge of the distribution
of the species. The analysis of the species activity showed that it uses a mosaic habitat structure,
but with a dominant share of deciduous forest habitats, within which stands of old beech (63%)
and oak trees (32%) dominate. The MaxEnt habitat suitability model identified temperature
bioclimatic variables as more significant than precipitation, with a significant contribution of
the proximity to water habitats. Matching the independent species presence data to higher
categories of modelled suitability was good, confirming the replicability of the model. Higher
suitability values of the model also matched with the researched localities for the presence of
the species, mainly in the beech and oak forests. Forest management measures were proposed
to achieve conservation of the bat populations connected to forest habitats
BIOLOŠKE I EKOLOŠKE ZNAČAJKE PORODICE CHIRONOMIDAE (INSECTA: DIPTERA) NA PODRUČJU DINARIDSKE EKOREGIJE HRVATSKE
No full textTrzalci (Diptera, Chironomidae) su jedna od najrasprostranjenijih i često najbrojnijih
skupina vodenih kukaca svih vodnih tijela, a koriste se u analizama procjene kvalitete vode.
Detaljnije istraživanje njihove ekologije i taksonomije je prijeko potrebno s obzirom na
njihovu indikatorsku važnost. Nacionalni park Plitvička jezera je odabran kao primarno
područje istraživanja, jer je moguće provesti sveobuhvatno i detaljno istraživanje biologije
i ekologije trzalaca. Na području Plitvičkih jezera ukupno je zabilježeno 116 vrsta trzalaca
čime je ukupan broj vrsta u Hrvatskoj povećan na 258. Utvrđeno je produljenje faze leta
trzalaca te promjene u sastavu zajednice kao rezultat zatopljavanja i ekstremno visokih
protoka koji postaju učestaliji zbog globalnih klimatskih promjena. Osim toga, kroz izradu
novog indeksa kao metrike za procjenu stanja litorala dokazana je važnost trzalaca kao
indikatorske skupine. Time se ukazalo na važnost taksonomske rezolucije u zaštiti i
upravljanju stajaćicama, čijom primjenom se mogu poboljšati postojeći modeli procjene
ekološkog stanja ekosustava.Chironomids (Diptera, Chironomidae) are widely distributed and often among the most
abundant aquatic insects used in water quality analysis. Knowledge of their ecology and
taxonomy should be studied in detail due to their significance as indicators in aquatic
ecosystems. Plitvice Lakes National Park was chosen as a primary study area due to
minimal anthropogenic influence and it is possible to have a comprehensive and detailed
study of chironomid biology and ecology. At the end of this study a total of 116 chironomid
species were recorded in the Plitvice Lakes raising total abundance of chironomid species
in Croatia to 258. It was also detected that chironomid flight period extended due to higher
water temperatures. A change in the chironomid community composition was also
observed and atributed to extreme discharges facilitated by climate driven changes. In the
end, Lake Chironomid Index was developed in order to address the importance of high
taxonomic resolution in freshwater bioassessment which has the potential of improving
already existing bioassessment models
The presence of nitrogen compounds in the groundwater of the inflow area of the Strmec well field
No full textU ovom završnom radu definirana je prisutnost dušikovih spojeva u priljevnom području crpilišta Strmec. Određeno je da su nitrati dominantna forma dušikovih spojeva u podzemnoj vodi crpilišta Strmec. Također, testirano je koji parametri utječu na koncentracije nitrata u podzemnoj vodi i koliki je antropogeni utjecaj na koncentracije nitrata. Statističke metode korelacije i regresije korištene su za definiranje odnosa između promatranih varijabli, a rezultati su prikazani dijagramima izrađenim u MS Excelu i softveru Tibco Statistica (14.0.0.15). Dobiveni rezultati kod dijagrama raspršenja prikazuju da se povišenjem električne vodljivosti povisuje i koncentracija nitrata, nešto manje kod otopljenog kisika u vodi i još manje kod pH vrijednosti, a kod povišenja temperature se smanjuje. Izvori onečišćenja i povišenja koncentracija nitrata mogu biti utjecaj poljoprivrede, nepravilno odlaganje otpada ili neki drugi čimbenici.In this Final Seminar, statistical methods were used to determine how different parameters affect the presence of nitrogen compounds in the inflow area of the Strmec well field. It was determined that nitrates are the dominant form of nitrogenous compounds in the underground water of the Strmec well field. It was tested which parameters affect nitrate concentrations in groundwater and how much anthropogenic influence there is on nitrate concentrations. Different piezometers capture different depths of the alluvial aquifer, and the concentrations of parameters and nitrates change. Correlation and regression statistical methods were used to determine the relationship between the observed variables and the results were presented with diagrams created in MS Excel and Tibco Statistica software (14.0.0.15). The obtained results in the scatter diagrams show that the increase in electrical conductivity also increases the concentration of nitrates, slightly less in the case of dissolved oxygen in water and even less in the pH value, and decreases in the case of an increase in temperature. Sources of pollution and increased nitrate concentrations can be the influence of agriculture, improper disposal of waste or some other factors
PHYSIOLOGY OF DIGESTION IN BALKAN SNOW VOLE Dinaromys bogdanovi (V. et E. Martino, 1922)
No full textDinarski voluhar (Dinaromys bogdanovi) je mali biljojedni glodavac, endem Balkanskog poluotoka i strogo zaštićena vrsta u Hrvatskoj. Cilj istraživanja bio je proučiti prilagodbe žvačnog sustava, morfološke i histološke karakteristike probavnog sustava, brzinu probave i sposobnost probavljanja kod ove vrste. In vivo mjerenja sile ugriza pokazala su očekivane vrijednosti s obzirom na tjelesnu masu, s većim vrijednostima kod ženki. Anatomska analiza žvačnih mišića otkrila je da m. masseter profundus anterior i m. temporalis anterior najviše doprinose ukupnoj masi aduktora čeljusti. Morfološka i histološka analiza probavnog sustava otkrila je specifične prilagodbe u strukturi tipične za potporodicu Arvicolinae. Istraživanje brzine probave pokazalo je da dinarski voluhar koristi mehanizam kolonske separacije poznat kao "mukozna zamka" za zadržavanje tekuće frakcije probave i mikroorganizama, ključnih za fermentaciju i apsorpciju hranjivih tvari. Rezultati pokazuju visoku efikasnost probave i apsorpcije hranjivih tvari, s razlikama između spolova. Ovo istraživanje doprinosi razumijevanju fiziologije probave dinarskog voluhara, pružajući prve uvide u morfološke i fiziološke karakteristike probavnog sustava ove vrste, koje ukazuju na specijalizaciju prema biljojednoj hranidbi.The Balkan snow vole (Dinaromys bogdanovi) is a small herbivorous rodent, endemic to the Balkan Peninsula and classified as a strictly protected species in Croatia. This study examined adaptations of the masticatory system, as well as the morphological and histological characteristics of the digestive system, digestion rate, and digestibility of this species. In vivo bite force measurements showed expected values relative to body mass, with higher values in females. Anatomical analysis of the masticatory muscles revealed that the m. masseter profundus anterior and m. temporalis anterior contribute most to jaw adductor mass. Morphological and histological analysis of the digestive system revealed specific adaptations typical of the subfamily Arvicolinae. Digesta passage rates confirmed a mucus trap colonic separation mechanism, retaining the liquid fraction and microorganisms crucial for fermentation and nutrient absorption. The results indicate high efficiency in digestion and nutrient absorption, with sex-related differences. This research contributes to the understanding of the digestive physiology of the Balkan snow vole, providing the first insights into the morphological and physiological characteristics of it's digestive system, which indicates specialization towards a herbivorous diet
Modeliranje koncentracije lijeka u krvnim žilama kojeg ispuštaju stentovi
No full textU ovom diplomskom radu matematičkim modelom opisujemo otpuštanje lijeka iz ovojnice stenta u stijenku krvne žile. U prvom poglavlju kreiramo geometriju stenta i stijenke krvne žile pomoću alata Gmsh te generiramo mrežu konačnih elemenata na dobivenoj geometriji. U drugom poglavlju formuliramo jednadžbu advekcije-difuzije koja opisuje naš model, zadajemo početne i rubne uvjete te izvodimo slabu formulaciju zadaće. U trećem poglavlju diskretiziramo vremensku domenu, definiramo parametre zadaće te radimo adaptaciju vremenskog koraka. Naposljetku rješavamo zadaću koristeći alat FreeFEM++ i prikazujemo i analiziramo rezultate numeričkih simulacija.In this Master Thesis, we describe drug release from the stent coating into the arterial wall using a mathematical model. In the first chapter, we create geometry of the stent and blood vessel wall using the Gmsh tool and generate a finite element mesh on the resulting geometry. In the second chapter, we formulate the advection-diffusion equation that describes our model, set the initial and boundary conditions, and derive the weak formulation of the problem. In the third chapter, we discretize the time domain, define the parameters of the problem, and adapt the time step. Finally, we solve the problem using the FreeFEM++ tool and present visualizations and analyze the results of the numerical simulations
MODELLING PHYSIOLOGICAL PROCESSES USING THE DYNAMIC ENERGY BUDGET THEORY TO SUPPORT SUSTAINABLE MARINE RESOURCE MANAGEMENT
No full textPredviđanje fiziološkog odgovora organizama na okolišne uvjete temelj je sustava informiranja upravljanja živim prirodnim resursima. Povezivanje fizioloških procesa jedinke s okolišnim uvjetima u kojima se ona nalazi stoga je od ključnog značaja, osobito u kontekstu klimatskih promjena. Teorija Dinamičkih Energijskih Proračuna (Dynamic Energy Budget, DEB) jedinstveni je konceptualni okvir koji povezivanjem saznanja o unosu, protoku i iskorištavanju energije unutar organizma pruža osnove za razvoj modela za predviđanje utjecaja niza okolišnih čimbenika na individualne procese rasta, sazrijevanja i razmnožavanja. U ovom je radu istražen potencijal DEB modela kao alata za informiranje aktivnosti upravljanja morskim resursima – očuvanja vrsta, marikulture i ribarstva – kroz razvoj i adaptaciju modela za tri reprezentativna organizma – plemenitu perisku, komarču i srdelu. Rezultati pokazuju kako simulacije modela u sva tri slučaja pokazuju vrlo dobro poklapanje s postojećim mjerenim podacima, a dodatna integracija okolišnih podataka, kao što su temperatura i količina hrane, poboljšava sposobnost modela za predviđanje rasta i reprodukcije u promjenljivim uvjetima. Integracija DEB modela jedinke u populacijski model temeljen na jedinkama (individual-based model, IBM) omogućuje predviđanje dinamike populacije i njenog odgovora na vanjske uvjete, dobivanje uvida u poveznice između svojstava jedinke i njene populacije, te istraživanje mehanizama povratnih sprega ove dvije razine. Povezivanje razvijenog DEB modela s platformom geografskog informacijskog sustava dodaje prostornu dimenziju, te daje mogućnost lokalno specifičnog modeliranja fiziologije organizama na široj prostornoj skali. Primjenom tog pristupa na vremenske nizove projekcija okolišnih uvjeta kao funkcije klimatskih promjena, stvorena je mogućnost vremensko-prostornih predviđanja utjecaja klimatskih promjena na organizme i populacije od interesa. Razvijene modele, kao i spoznaje proizašle iz rezultata, moguće je integrirati u postojeće prakse informiranja i donošenja odluka i mjera, a daljnjom nadogradnjom teži se uspostavi novih sustava potpore održivom upravljanju morskih resursa.The management of living natural resources relies on predicting the physiological responses of organisms to environmental conditions. Relating the physiological processes of the individual to the surrounding environmental conditions is crucial, especially in the context of climate change. The Dynamic Energy Budget (DEB) theory is a unique concept that consolidates knowledge about the intake, flow and utilization of energy within the organism, providing a framework for modelling the effects of various environmental factors on individual processes of growth, maturation and reproduction. This study explores the potential of DEB models as tools for informing marine resource management activities - species conservation, mariculture, and fisheries - through the development and adaptation of models for three representative organisms – the noble pen shell, gilthead seabream, and sardine. The results demonstrate a strong alignment between the model simulations and measured data, while the additional integration of environmental data, such as temperature and food availability, improves the model's ability to predict growth and reproduction under variable conditions. Integrating the DEB model into an individual-based population model (IBM) enables the prediction of population dynamics and their response to external conditions, providing insights into the connections between individual and population characteristics, as well as investigating the feedback mechanisms between these two levels. Combining the developed DEB model with the geographic information system adds a spatial dimension, allowing for locally specific modeling of organism physiology on a broader spatial scale. Applying this approach to climate-change-driven projections of environmental conditions allows for a temporal-spatial predictions of the impact of climate change on organisms and populations of interest. Existing informing and decision-making practices benefit from the integration of developed models and newly derived knowledge, with further upgrades aiming to establish new support systems for the sustainable management of marine resources